The instant inventors have revealed that a bi-cyclic compound such as
7-[(2R,4aR,5R,7aR)-2-(1,1-difluoropentyl)-2-hydroxy-6-oxooctahydrocyclopenta[b]pyran-5-yl]heptanoic acid is useful for treating or preventing constipation and the stability of the compound can be improved by admixing the same with a glyceride (see WO2001/027099 (U.S. Pat. No. 6,583,174) and WO2002/020007 (U.S. Pat. Nos. 6,414,016 and 6,610,732), the contents of these references are herein incorporated by reference.).
To date, there is no information about how a solvent other than glyceride affects on the stability of the bi-cyclic compound.